Project of a specialized mass spectrometer for precision mass measurement of superheavy elements at the Factory of Superheavy Elements at the Joint Institute for Nuclear Research (JINR) in Dubna is presented in the paper. The mass spectrometer is intended for achieving the mass accuracy of 10–7 at a low statistics (~5 events). The key part of the mass spectrometer is a new generation multi-reflection time-of-flight mass analyzer. To prepare and separate the probe and calibrant, a set of new ion-optical elements is implemented in the spectrometer, such as a radio-frequency selector of the state of charge, quadrupole mass filters operating in the beat node coincidence mode, a collision dissociation cell with beam focusing in the gap of a vacuum valve, and a source of calibration ions with electron ionization of fullerene soot. [ABSTRACT FROM AUTHOR]